Container or platter assembly having locking and release features

Abstract

A polygonal lid and container base provide secure and reliable engagement therebetween, while also facilitating removal of the lid without disturbing contents and without applying undue stress to the lid. The lid includes at least one graspable member near or at a designated “release” vertex that facilitates disengagement of the lid from the container base at the release vertex. The lid further includes regions of enhanced engagement that enhance the attachment of the lid to the container base at least along the two sides of the lid that adjoin the release vertex, causing the overall attachment to be less dependent on attachment at the release vertex. As a result, the strength of attachment at the release vertex can be made weaker than at the other vertices, for easy release of the release vertex, without undue weakening of the overall attachment of the lid to the container base.

What is claimed is: 
     
         1 . A container assembly including a polygonal lid and a polygonal container base, the lid being adapted for engagement with and easy release from the container base, the container assembly comprising:
 a container base having a container bottom wall, a container sidewall that extends upwardly and outwardly from said container bottom wall, and a peripheral container rim that is substantially polygonal in shape;   a lid having a lid top and a lid engagement feature proximal to a peripheral lid rim, said peripheral lid rim being substantially polygonal in shape, said lid engagement feature being configured for mutual cooperation and attachment with the peripheral container rim of the container base, thereby forming a container assembly, the peripheral lid rim including a vertex that is designated as a release vertex;   at least one graspable member provided in said lid proximal to the release vertex of the peripheral rim, said graspable member being configured for disengaging the release vertex from the peripheral container rim; and   at least one region of enhanced engagement included in each side of the peripheral lid rim and at least one cooperating region of enhanced engagement included in each side of the peripheral container rim, said regions of enhanced engagement in the peripheral lid rim along with said cooperating regions of enhanced engagement in the peripheral container rim collectively ensuring a secure attachment between the container base and the lid, thereby avoiding or impeding unintentional disengagement between the tray and the lid during at least one of handling, transporting, and carrying said container assembly.   
     
     
         2 . The container assembly of  claim 1 , wherein said lid engagement feature provides weaker engagement with the container base in a region encompassing the release vertex of the peripheral rim, as compared to regions of the engagement feature that encompass other vertices of the peripheral rim. 
     
     
         3 . The container assembly of  claim 1 , wherein said lid engagement feature comprises a peripheral groove extending substantially continuously about the peripheral rim, said peripheral groove being configured for mutual cooperation and attachment with the container base by receiving said peripheral container lip of the container base therein. 
     
     
         4 . The container assembly of  claim 3 , wherein the peripheral groove is deeper in the enhanced engagement regions of the peripheral rim as compared to other regions of the peripheral rim. 
     
     
         5 . The container assembly of  claim 1 , further comprising regions of modified shaping of the lip of the container base that cooperate with the regions of enhanced engagement of the peripheral rim of the lid to strengthen the engagement of the lid with the container base in the regions of enhanced engagement. 
     
     
         6 . The container assembly of  claim 1 , wherein the graspable member is provided in a peripheral skirt of the lid. 
     
     
         7 . The container assembly of  claim 6 , wherein said peripheral skirt is configured for guiding said base peripheral container lip into cooperation with said lid engagement feature and facilitating formation of said container assembly; and
 the peripheral skirt is sufficiently short to enable a user to lift the container base from below when the lid is engaged with the container base.   
     
     
         8 . The container assembly of  claim 6 , wherein said peripheral skirt extends between 0.1″ and 0.3″ below said peripheral container lip of said container base. 
     
     
         9 . The lid according to  claim 6 , wherein said peripheral skirt extends about 0.2″ below said peripheral container lip of said container base. 
     
     
         10 . The container assembly of  claim 1 , wherein the graspable member is a lift tab. 
     
     
         11 . The container assembly of  claim 1 , further comprising a visible indication cooperative with the graspable member, said visible indication being an indication that suggests lifting of the graspable member. 
     
     
         12 . The container assembly of  claim 1 , further comprising a press area proximate to said graspable member and located relatively inwardly from said lid engagement feature, said press area being downwardly pressable by a hand of a user while said hand is lifting said graspable member, thereby disengaging the release vertex from the lip of the container base. 
     
     
         13 . The container assembly of  claim 12 , further comprising a visible indication cooperative with the press area, said visible indication being an indication that suggests pressing on the press area while lifting the graspable member. 
     
     
         14 . The container assembly of  claim 1 , wherein said lid is dome shaped. 
     
     
         15 . The container assembly of  claim 1 , wherein the graspable member is located at the release vertex of the lid. 
     
     
         16 . The container assembly of  claim 1 , wherein a pair of graspable members are located adjacent to either side of the release vertex. 
     
     
         17 . The container assembly of  claim 16 , wherein said graspable members are simultaneously operable with a user's left and right hands respectively. 
     
     
         18 . The container assembly of  claim 16 , wherein said graspable members are sequentially operable with at least one of a user's hands. 
     
     
         19 . The container assembly of  claim 1 , wherein said container base is a substantially flat tray. 
     
     
         20 . The container assembly of  claim 1 , wherein the material of construction of the lid is one of: polypropylene (PP), oriented polystyrene (OPS), polyethylene terephthalate (PET), styrene butadiene copolymer, and rubber modified styrene. 
     
     
         21 . The container assembly according to  claim 1 , wherein said lid is made by a thermoforming process. 
     
     
         22 . The container assembly according to  claim 1 , wherein said lid is thermoformed from an oriented polystyrene sheet.